Objective: To examine the relationship between patterns of use of inhaled beclomethasone dipropionate and the risk of fatal and near-fatal asthma.
Design: Nested case-control analysis of a historical cohort; a further analysis.
Setting: The 12,301 residents of Saskatchewan aged 5 to 54 years who were dispensed 10 or more asthma drugs from 1978 to 1987.
Patients: The 129 persons who experienced asthma death (n = 44) and near-death (n = 85) and their 655 controls matched as to age and date of entry into the cohort, with the additional matching criteria of at least one hospitalization for asthma in the prior 2 years, region of residence, and having received social assistance.
Main outcome: Life-threatening attacks of asthma defined as death due to asthma or the occurrence of hypercarbia, intubation, and mechanical ventilation during an acute attack of asthma.
Results: After accounting for the risk associated with use of other medications and adjustment for markers of risk of adverse events related to asthma, subjects who had been dispensed, on average, one or more metered-dose inhalers of beclomethasone per month over a 1-year period had a significantly lower risk of fatal and near-fatal asthma (odds ratio, 0.1; 95% confidence interval, 0.02 to 0.6).
Conclusion: These data support recent guidelines from several countries that recommend the use of inhaled corticosteroids in moderate and severe asthma.